查询词典 momentum

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory.

本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory. The key techniques used in numerical simulation of the three-dimensional extrusion from dies such as decision of boundary conditions, creation of initial velocity field, selection of penalty factor, high Weissenberg number problem , regeneration of the free surface were studied in detail.

中文题名聚合物异型材口模挤出三维流动研究副题名外文题名 Study on three-dimensional flow of polymer melts during the process of profile extrusion from dies 论文作者涂志刚导师柳和生包忠诩教授学科专业材料加工工程研究领域\研究方向学位级别博士学位授予单位南昌大学学位授予日期2001 论文页码总数148页关键词挤出成型聚合物材料挤出口模聚合物异型材馆藏号BSLW /2003 /TQ320 /9 本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

Our house attractive Phoenix Mountains Crescent, built on the momentum and build, occupy a commanding position, implies it is a few kilometres you, the Chinese parasol tree forest woodland hill ;11 metres high household hall along to exhibit honorable, the entrance point magnificent large water screen Falls, flyings feet jade, it rains cool; Western-style pavilion, luxury clubs, rooftop swimming pool, Roman sculpture, secluded Department, more water flows; Wu Dong China and the United States in the deep green onions noble buildings show the Mid-Levels, which is a constellation of 12 creative theme of the West Cottage Fung Tsui Court.

背靠苍翠秀丽的凤凰山畔，依山就势而建，居高临下，极目之处是绵延数公里、森林茂密的梧桐山；11米高的住户大堂气势磅礴，彰显尊贵，入口之处蔚为壮观的大型水幕瀑布，飞花溅玉，似梅雨清凉；西式凉亭、豪华会所、天台泳池、罗马雕塑，曲径通幽处，更有流水潺潺；五栋华美高贵建筑物点缀在苍葱的半山，这就是按西方十二星座为创意主题的庐峰翠苑。

In order to demonstrate that it is possible to use two reverse rotating flywheels to simultaneously provide energy storage and attitude control in a single axis, a kind of integrated energy storage and attitude control system composed of bias momentum wheels was researched by theory analysis and simulation.

为了验证在同一轴上安装两个反向旋转飞轮能够同时完成能量存储与姿态控制问题，对一种由偏置动量轮构成的集成化单轴储能及姿态控制系统进行了理论分析及仿真研究。

Based on equations of continuity and momentum balance in the liquid-solid circulating moving bed reactor,a stress distribution model was established to study stress distribution and flow patterns in the reactor,which took into account weight of liquids,buoyancy of liquids to solids,supporting force of wall in conical bed and friction force of wall.

为研究循环移动床反应器的应力分布和颗粒流动状态，建立了由流体相及固相质量连续方程和动量守恒方程组成的循环移动床反应器模型，考虑了流体质量、流体对固相产生的浮力、锥形床边壁对颗粒的支撑作用以及壁面摩擦力的影响。

In the Franco-Italian border of Western Europe's highest peak Mont Blanc --- 4807 meters above sea level, in the northern end of Mont Blanc has a long 1,400 km, 14 km wide, 400 m thick ice momentum magnificent area.

在法意边界有西欧最高峰———海拔4807米的勃朗峰，在勃朗峰的北端有一条长1400公里、宽14公里、厚400米的气势壮阔的冰河区域。

The main point is to understand the momentum space structure of the systemat freeze-out in order to extract information about earlier stage of the collision.

相对论重离子碰撞中的集合流和两粒子干涉学之间的关系是一个重要的研究课题，其主要研究目的是为了从冻结时刻相空间中提取有关碰撞早期阶段的的信息。

These main methods were as follows: the local officials themselves heard the cases, got the causes, tried to persude the believers and the common people ,otherwise punished them to suppress their critical momentum to reduce resistance; relied on local rural Managers and gentries to settle the cases; argued vigorously with priests and believers according to treaties; consulled directly with the minister and rejected the unreasonable demands ;noticed out to tell the people and so on.

直隶地方官员们利用近代的外交手段并传统办案的方法加以解决教案的交涉，主要方法有亲身审问，当堂直接讯明案情根由；劝谕开导、刚柔并济对民教详加开导进行说理工作，否则刑责教民，压制其气势减少办案阻力；借助地方乡保、士绅等人之力而结案；派员会办，查明根由；对教士教民以进为退据约力争；与公使领事直接会商驳斥开导；出谕晓示以通民教之情等等。

It is proved through the experimentation that adopting these technique can obviously improve the control precision of the reaction wheel's velocity and obviously minish the angle momentum output of the two-axis gimbals mechanism on the satellite.

结合反作用轮的控制模型，在双闭环控制结构上，加入了前馈控制和死区电压补偿。通过实验证明，采用这些技术，可以显著提高反作用轮转速的控制精度，大幅度减少星载二维转台的角动量输出。

Indeed, this strong golden-yellow finish is truly fascinating both in the glow of headlights from other vehicles and in the bright sunshine, creating a highly effective play of light and adding additional momentum to the artistically chiselled surfaces of the BMW X1 Concept.

事实上，这种强烈的金黄色的成绩确实是令人着迷无论是在与其他车辆前灯发光，在明亮的阳光，创造高效光游戏和增加额外的动力艺术轮廓清晰的宝马X1概念表面。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。